The former marine, who was born to a Scottish mother and American father, moved back to Scotland for a period but then returned to Tupelo, Mississippi, where he was arrested and jailed for three years in 2012.

On the website he states: “After 5 heart attacks and 1 stroke, I find myself almost 40,000 US dollars in debt, with no health or medical insurance and no income. I can’t pay for my heart medication. I am now homeless and desperate.

“I spent 21+ years on Death Row, waiting to die in the electric chair for a crime I didn’t commit. I won my freedom in 2008.

“I have had a hard time trying to adjust to the norms of society and do not know how to function properly. I need medical care and treatment but can’t afford it.

“I am trying to return home to Scotland, where I would be better able to get that care. I am a 51-year-old man with nowhere to live, struggling to survive. I need help as quick as possible.”

Richey told BBC Radio Scotland that since his release from prison “everything’s gone from bad to worse” and he had spent the past week sleeping on the steps of a church.

He told the Stephen Jardine programme: “I want to come back because it’s my home.

“It’s my home, it’s my country, I wouldn’t mind finding some place quiet, maybe out in the countryside somewhere, away from everybody, I’d be happy with that.”

Richey, who said he has a girlfriend in Scotland, added: “It’s my home, I’m dying, I want to die in Scotland. They gave me two years to live six years ago. I just want to come home.”

However, he said he did not think many people would help him, saying: “Everybody in Scotland has made their bloody mind up about me, they always look at me like I’m a piece of trash or something, that I’m scum. They don’t see the human side of me.”

He urged people to “walk a mile in my shoes, live the kind of life I’ve lived, live the pain and misery I’ve gone through” before judging him

“I feel very bitter towards the system, how it’s treated me, what it’s done to my life,” he said. “I’ve lost everything, I’ve lost my youth, lost my health, and life sucks.”